Rivers, wetlands, lakes, and the life that relies on them, are at risk around the world because of a variety of stresses, including overuse of water, pollution, introduction of exotic species, and overfishing, according to the new study, published today in the journal Nature.

The study maps out all of these stresses and nearly two dozen more; it is the first such detailed map of the threats to human water security and river biodiversity. (See our rivers photogallery.)